AB0005 CHANGES OF SALIVARY MICROBIAL COMMUNITY IN PATIENTS WITH PERIODONTITIS
Authors: C. Wang, J. Qiao, Y. Li, M. J. Chang, R. X. Qi, S. X. Zhang, Q. Yu, P. F. He
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Periodontitis (PD) is a chronic, progressive polymicrobial disease<sup>[1]</sup>. In the context of the microbiome in the pathogenesis of rheumatic disease, microorganisms located in the periodontal tissues play an important role as potential initiators of immune-mediated inflammatory conditions at distant sites<sup>[2]</sup>. Studies have shown that the microbiota associated with PD is different from that in health, and the chronic inflammatory response induced by salivary microbiota plays an important role in the development of PD. <h3>Objectives</h3> Study to evaluate and quantify the differences in the composition of salivary microbiota in patients with PD, and investigate the correlation between salivary microbiota in patients with PD and clinical variables. <h3>Methods</h3> In the same race, 34 salivary samples of patients with PD and 28 salivary samples of periodontal health controls(HC) were collected for 16S rRNA gene sequencing. Compare salivary microbiota alpha-diversity,beta-diversity and microbial composition (at the phylum and genus levels) were used to determine differences in salivary microbiota characteristics between periodontitis patients and periodontal health controls. LefSe analysis was carried out to identify differentially abundant genera.The correlation between different taxa and clinical variables was calculated by the Spearman rank test. <h3>Results</h3> Consistent with the observed diversity trend, compared with periodontal health, the richness of patients with periodontitis is relatively high (P&lt;0.05, Figure 1a), which indicates that the diversity of salivary microbiome in patients with periodontitis is significantly higher. The Beta diversity based on Bray Curtis distance at the species level demonstrated a significant differences in microbial communities between periodontitis patients and periodontal health (analysis of variance, r2=0.094, p=0.001,Figure 1b). At different phylogenetic levels, the 10 selected taxonomic biomarkers showed strong discrimination ability, with log10 LDA score &gt;4.0 (Figure 1e-g). Specifically, at the phylum level, the Firmicutes phylum frequency of periodontitis patients is lower, while the Spirochaetota frequency is higher. Patients with periodontitis have more genus Treponema at the genus level (Figure 1c-d). PICRUSt analysis found that in the KEGG pathway, the function of microbial genes related to amino acid metabolism in the salivary microbiota of periodontitis patients was higher (Figure. 1h). Treponema was positively correlated with periodontal probing depth (PPD). Total, plaque index (PI) and periodontitis extent Calc. Spirochaetota was positively correlated with PPD Total, PI (p&lt;0.05, Figure 1i). <h3>Conclusion</h3> Specific salivary microbiota played an important role in the pathogenesis of periodontitis, which may help to diagnose or determine individual susceptibility to periodontitis by detecting salivary microbiota. <h3>References</h3> [1]Belkaid Y, Hand T W. Role of the microbiota in immunity and inflammation[J]. Cell, 2014,157(1):121-141. [2]de Molon R S, Rossa C J, Thurlings R M, et al. Linkage of Periodontitis and Rheumatoid Arthritis: Current Evidence and Potential Biological Interactions[J]. Int J Mol Sci, 2019,20(18). <h3>Acknowledgements</h3> This work was supported by the Key R&amp;D Program of Shanxi Province(201903D311011) and Taiyuan Science and Technology Plan (XG2020-5-06). <h3>Disclosure of Interests</h3> None Declared.